Gen 1.3: Troubleshooting Nozzles Not Misting

This article covers how to diagnose the issue of nozzles not misting on a Gen 1.3 Drum unit, as well as going over the troubleshooting/repair process to determine the failed component and ultimately fix it.

 

See Gen 1.3:  Controller displays “MIST”, but Nozzles Not Misting

 

Troubleshooting Steps:

 

1.  Check internal contents of drum

• Remove drum lid and confirm liquid level in drum is at or above intake filter and that filter is clean
  • If liquid level is low, add water
  • If filter is clogged, clean and replace
• Check that pump intake line is secure
  • If pump intake pipe isn’t secure, push it up all the way into the fitting
• Make sure the Auto-drain valve is attached
  • If the valve is missing, the unit will be unable to produce pressure. Either replace the valve or, for a temporary substitute, install a nozzle on the Auto-drain line using a 1/4″ coupling
    • The latter option is not recommended as a permanent solution
• Run INSpect. If nozzles not misting, continue troubleshooting

2. Confirm motor is in working condition

• Run INSpect and listen for the motor relay click
  • If you don’t hear a click at the beginning of the mist, the cause is probably either: 1) controller relay failure or 2) motor failure
  • If you do hear a click, then the motor relay on the controller is in good condition. Continue troubleshooting
• Disconnect the pump from the motor by removing the cat clamp. With the pump isolated, grasp the grey, square metallic piece of the pump that interlocked with the motor shaft and attempt to turn it by hand.
  • If the pump is difficult to turn by hand or completely seizes up after 1-2 turns, then the issue is the pump and will require a replacement.
  • If the pump spins with little to no resistance, then proceed to testing the motor
• With the pump still disconnected from the motor, run an INSpect and observe the motor shaft
  • If the motor shaft does not spin, or if it spins but the motor reaches extreme levels of heating, then the problem is either the motor or the motor cable and it is recommended to replace both as a precaution
  • If the motor shaft spins and the motor does not reach excessive levels of heat, then the motor is not the issue. Continue troubleshooting

3.  Confirm pressure gauge is working and pressure is nominal during INSpect

• First, check the pressure gauge while the system is idle (not doing anything)
  • The pressure gauge should always read 0 psi in this state
  • If it reads anything but 0 psi, the pressure gauge has failed and will need to be replaced before proceeding with pressure related problems
• Run an INSpect mist
  • If the pressure is in the system’s normal operating range of 220 – 250 psi and you have low mist, the cause is either:
    • Fouled nozzles
    • A blockage or kink somewhere in the nozzle circuit
    • A partially open Agitation Valve.
  • If pressure is lower than 200 psi, continue troubleshooting

4.  Run INSpect, then kink the 1/4″ nozzle circuit tubing just outside of the unit and observe pressure gauge

• If the pressure increases to 250 psi or more, the cause of your nozzles not misting is either:
  • A leak in the nozzle circuit
  • The nozzle circuit has too many nozzles and exceeds the capacity of the pump (about 100 nozzles in total and 1000 feet of tubing)
• If the pressure is less than 200 psi with the line kinked, continue troubleshooting

5.  Run INSpect, reduce the flow bypassed by the pump with a flathead screwdriver (turning the screw clockwise) and observe pressure gauge

• If the pressure increases in response to closing the bypass, the probable cause is that the pump bypass was too open for the size of the nozzle circuit. Do not increase the pressure higher than 250 psi
• If the pump bypass is completely closed and the pressure is less than 200 psi, return bypass screw to original position and continue troubleshooting

6.  Confirm whether the agitation valve is working

• Remove the first nozzle by unscrewing the tip from the nozzle assembly, then run an INSpect
  • If fluid shoots out of the open nozzle assembly, then fluid is flowing through the agitation valve as expected. Proceed to step 7
  • If no fluid shoots out of the open nozzle assembly, then the Agitation Valve is not opening during the INSpect like it should
• If the Agitation Valve is not opening during INSpect, the probable causes are either:
  • An unplugged Agitation Valve connector from the back of the controller (Two-pronged white connected with a red-dot sticker on it)
  • A mechanical failure of the valve, which necessitates a replacement of the Agitation Valve
  • Low voltage from the outlet, which can be checked using a digital voltmeter/multimeter both at rest and at the time of misting (looking for 115 – 120 Volts). If low voltage is confirmed, an electrician will have to be consulted

7. Pump failure and replacement

• If all of the tests above have passed without a solution, then the most likely cause of the low mist problem is a failing or failed pump.  See Gen 1.3:  Replace Pump